The ten-lined June beetle (Polyphylla decemlineata), also known as the watermelon beetle, is a scarab beetle, living in the western United States and Canada. The adults are attracted to light and feed on foliage. They can make a hissing sound when touched or otherwise disturbed, which can resemble the hissing of a bat. This sound is made by their wings pushing down, forcing the air out between their wings and back. They can be an agricultural pest affecting a wide range of crops because their larvae feed on plant roots and can weaken or kill the plants.